PATELLA. 259 



tacula are white, shortish, rounded, tumid at the bases, taper- 

 ing, but not to a fine point, setose, and in young animals 

 there is a transparent line from base to point ; the eyes are 

 small, at the external bases, though raised a little on them. 

 The foot, Avhen at rest, is nearly a regular oval, but in action 

 becomes greatly elongated, and often puckered anteriorly ; 

 the sole is yellowish- white, edged by a fine brown line, and on 

 the upper surface has a clouding of bistre hues. No exserted 

 organe generateur is seen in this group, therefore the animal 

 belongs to that category which is styled " self-sufficient." This 

 term requires some explanation. 



.All the Conchifera, PateUce and Chitons, notwithstanding 

 this deficiency, have well-filled ovaria in the genial season ; 

 but that is not sufficient without a communion of both the 

 sexual influences, which, though they may exist in the same 

 body, must be essentially distinct. It will be asked, where, 

 and what, are the male organs of this tribe ? If the animals 

 are examined when the " genitabilis aura Favoni " impresses 

 ah 1 nature with its magic influence, they will be found to be full 

 of ova, mixed with a milky fluid, which under the microscope 

 will appear to proceed from minute membranous bodies inter- 

 spersed or attached to the ovarmm ; these organs may furnish 

 the vital powers ; but we have searched in vain for them when 

 the ova are in a more advanced state. I have also observed 

 these phenomena in Dentalium Tarentinum. 



It is only agreeably to the foregoing conditions that I admit 

 the doctrine of self-sufficiency. I do not believe that a myste- 

 rious, invisible, and unknown principle, contrary to nature as 

 handed down to us, and independent of sexual union, exists in 

 this, or any other class ; the gemmae of the Polypi and scis- 

 sions of the Monads are not exceptions. I believe that a 

 universal law has impressed a distinct sexual union on all 

 animated nature. It is in this sense only that animals suffice 

 for themselves; that is, they must as fully exercise their 

 peculiar, though united, male and female influences, as if 

 they were bisexual ; I therefore consider the hermaphroditism 

 of this group of that character which I have already desig- 

 nated, Venus sine concubitu. 



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